What is the coefficient of the second term in the expression?

3a - 9b + 12c - 15d

A) -

B) b

C) - 9

D) - 9b

C) - 9

This is because the coefficients can be defined as the numbers before the variables. In this case the second variable reading from left to right is b. The coefficient (number I front of the variable) is negative nine which is answer choice C